But Portugal could issue a European arrest warrant a fast-track extradition process requiring no hard evidence of guilt.

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Critics also say it is unfair the US authorities need only to outline the alleged offence, and provide "evidence or information that would justify the issue of a warrant for arrest in the UK" whereas British police must provide the American courts with evidence of "probable cause" if it wishes to extradite someone.

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Meanwhile, Palestinians have expressed anger at the issue of a warrant for the arrest of Marwan Barghouti, the head of Mr Arafat's Fatah movement in the West Bank, by an Israeli court.

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